Article

Identification of unique expression signatures and therapeutic targets in esophageal squamous cell carcinoma.

Pathogenetics Unit, Laboratory of Pathology, National Cancer Institute, Bethesda, USA. .
BMC Research Notes 01/2012; 5:73. DOI:10.1186/1756-0500-5-73 pp.73
Source: PubMed

ABSTRACT Esophageal squamous cell carcinoma (ESCC), the predominant histological subtype of esophageal cancer, is characterized by high mortality. Previous work identified important mRNA expression differences between normal and tumor cells; however, to date there are limited ex vivo studies examining expression changes occurring during normal esophageal squamous cell differentiation versus those associated with tumorigenesis. In this study, we used a unique tissue microdissection strategy and microarrays to measure gene expression profiles associated with cell differentiation versus tumorigenesis in twelve cases of patient-matched normal basal squamous epithelial cells (NB), normal differentiated squamous epithelium (ND), and squamous cell cancer. Class comparison and pathway analysis were used to compare NB versus tumor in a search for unique therapeutic targets.
As a first step towards this goal, gene expression profiles and pathways were evaluated. Overall, ND expression patterns were markedly different from NB and tumor; whereas, tumor and NB were more closely related. Tumor showed a general decrease in differentially expressed genes relative to NB as opposed to ND that exhibited the opposite trend. FSH and IgG networks were most highly dysregulated in normal differentiation and tumorigenesis, respectively. DNA repair pathways were generally elevated in NB and tumor relative to ND indicating involvement in both normal and pathological growth. PDGF signaling pathway and 12 individual genes unique to the tumor/NB comparison were identified as therapeutic targets, and 10 associated ESCC gene-drug pairs were identified. We further examined the protein expression level and the distribution patterns of four genes: ODC1, POSTN, ASPA and IGF2BP3. Ultimately, three genes (ODC1, POSTN, ASPA) were verified to be dysregulated in the same pattern at both the mRNA and protein levels.
These data reveal insight into genes and molecular pathways mediating ESCC development and provide information potentially useful in designing novel therapeutic interventions for this tumor type.

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Keywords

cell differentiation
 
Class comparison
 
distribution patterns
 
esophageal cancer
 
IgG networks
 
molecular pathways mediating ESCC development
 
ND expression patterns
 
normal differentiated squamous epithelium
 
normal differentiation
 
normal esophageal squamous cell differentiation
 
patient-matched normal basal squamous epithelial cells
 
PDGF signaling pathway
 
protein expression level
 
squamous cell cancer
 
therapeutic targets
 
tumor cells
 
tumor type
 
tumor/NB comparison
 
unique therapeutic targets
 
unique tissue microdissection strategy